Compressible member for use in compression joint pipe connector

ABSTRACT

A re-useable compression type pipe connector comprises threaded male and female portions, a retaining ring and a sealing ring. The retaining ring has a hollow, truncated cone-shaped body portion with a plurality of circumferentially spaced-apart slits which extend in an axial direction inwardly from the smaller end of the retaining ring to define a plurality of gripping teeth. The sealing ring has a tubular shaped body portion, the axial length of the sealing ring being substantially longer than the axial length of the body portion of the retaining ring. The threaded portion receiving the end of the pipe has an annular inwardly-sloping surface which overlaps a portion of the retaining ring. The outside diameter of the sealing ring is such that the outside surface thereof slidably contacts the annular inwardly-sloping surface to exert an inwardly-directed force on the body portion of the retaining ring when the connector is assembled on a pipe. The gripping teeth are at a low angle relative to the pipe surface so that the gripping teeth do not substantially mar the pipe surface. An annular portion of the sealing ring which projects beyond the smaller end of the retaining ring is simultaneously moved radially inwardly by the annular inwardly-sloping surface so that the inside surface of the sealing ring intimately contacts the circumference of the pipe to form a fluid-tight seal therearound. The circumferential length of the free end of each gripping tooth is sufficient to provide substantially more than point contact with a pipe surface.

FIELD OF THE INVENTION

This invention relates to a re-useable compression type pipe connectorwhich releasably connects a pipe to another pipe or to a service outletto provide a fluid-tight seal therebetween.

BACKGROUND OF THE INVENTION

A problem often encountered in connecting a pipe to another piperequiring a fluid-tight seal, is providing a sealing device for the pipeconnector which readily conforms to the surface of the pipe to beconnected without damaging the exterior surface of the pipe. It isusually found that a pipe connector gouges or mars the exterior surfaceof the pipe to the extent that the connector cannot be reused on thepipe. Work in the field may entail disconnecting a pipe with subsequentreconnection. With a connector which substantially gouges or mars thepipe surface, a water-tight reconnection cannot be achieved, thereforethe damaged pipe end has to be cut off and a new connector used forreconnection. An example of such a connector is disclosed by Kody, U.S.Pat No. 3,29l,510, where the retaining ring meets the pipe surface at asubstantially high angle relative to the pipe surface and where thesealing ring exerts a force on the retaining ring in such a manner thatthe ring gouges the pipe surface.

It is therefore an object of the invention to provide a reusablecompression type pipe connector having a retaining ring and a sealingring. The connector releasably retains the pipe within the connector andeffects a fluid-tight seal around a pipe which has either a smooth wallor disconformities therein.

It is another object of the invention to provide a reusable compressiontype pipe connector wherein its retaining ring has gripping teeth whichmeet the pipe surface at a low angle. The portion of the connector whichreceives the pipe has an annular inwardly sloping surface overlapping aportion of the retaining ring to exert an inwardly directed force on theretaining ring to move the gripping teeth into contact with the pipe.This contact with the pipe retains it within the connector withoutsubstantially gouging or marring the pipe surface.

It is a further object of the invention to provide a reusablecompression type pipe connector wherein the circumferential length ofthe free ends of the gripping teeth are sufficient to providesubstantially more than point contact with the pipe surface so as topreclude gouging and marring of soft piping, such as plastic pipe.

SUMMARY OF THE INVENTION

These advantages and features of the invention are realized in providinga reusable compression type pipe connector comprising threaded male andfemale portions, one of which receives a pipe end, and a sealing andpipe retaining means. The retaining ring consists of a resilientmaterial having a hollow truncated cone-shaped body portion with aplurality of resilient gripping teeth, each having a free end. Thesealing ring consists of an elastomeric material and has a tubular shapewhich is substantially longer than the axial length of the retainingring. The sealing ring is in surrounding and contacting relationshipwith the outside surface of the retaining ring where the sealing ringcovers the slits between the gripping teeth in the retaining ring. Thegripping teeth of the retaining ring are disposed at a low anglerelative to the pipe surface, the angle ranging from approximately 5° to30°.

The threaded male or female portion which receives the pipe end has anannular inwardly sloping surface which engages the outside surface ofthe sealing ring when the connector is assembled on a pipe end. Theannular inwardly sloping surface overlaps a portion of the grippingteeth so that the sealing ring exerts an inwardly directed force on thegripping teeth to move them into contact with the pipe surface. Eachgripping tooth free end has a circumferential length to providesubstantially more than point contact with the pipe surface. Thearrangement of the components of the pipe connector is such that thegripping teeth free ends are precluded from substantially marring orgouging a pipe surface when the teeth are in contact therewith. Theconnector is therefore reusable in forming a fluid-tight seal around apipe end previously engaged by the connector.

The invention therefore provides a connector having a retaining ringwith resilient gripping teeth positioned at a low angle relative to thepipe surface. The annular inwardly sloping pipe surface of the male orfemale connector component overlaps a portion of the gripping teeth toprovide an inwardly directed force on the gripping teeth to move theminto contact with the pipe surface during assembly of the connector on apipe. The sealing ring surrounds the gripping teeth and covers the slitsof the retaining ring to provide a fluid-tight seal around the pipe. Thelow contact angle of the gripping teeth relative to the pipe surfaceprecludes the connector from substantially marring the pipe surface whenassembled so that the connector may be reused on a pipe end for purposesof a reconnection. Such a connector is not provided by Kody, U.S. Pat.No. 3,291,510.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, advantages and features of the invention willbecome apparent in the detailed description of the preferred embodimentsof the invention as shown in the drawings wherein:

FIG. 1 is an exploded view of a compression type pipe connectoraccording to a preferred embodiment of the invention;

FIG. 2 is a partially sectioned view of the compression type pipeconnector shown in FIG. 1 where the upper portion of the section showsthe connector partially assembled and the lower section shows theconnector assembled on a pipe; and

FIG. 3 is an enlarged view showing the angle of contact between theretaining ring and the surface of a pipe.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

A preferred embodiment of the invention is shown in the drawings. InFIG. 1 a connector 10 comprises a threaded male portion 12 and acorrespondingly threaded female portion 14. Each of the male and femaleportions has an axial bore to accommodate a pipe inserted therein in themanner shown in FIG. 2. The male portion 12 receives an end of a pipeand has an external thread 16.

The female portion 14 has an internal thread 18 which is adapted tothreadably engage the external thread 16 to advance female portion 14relative to male portion 12 upon positive rotation thereof. The femalemember 14 surrounds a pipe inserted in the male member 12 in the mannershown in FIG. 2.

The retaining and sealing means of the connector 10 comprises aretaining ring 20 and a sealing ring 22. The retaining ring 20 consistsof a resilient material, for example, 70/30 half hard yellow brass whichis deformable if stressed beyond its elastic limit. The retaining ringhas a tapered body portion 24 of the shape of a hollow truncated cone.In the body portion 24 there are a plurality of circumferentiallyspaced-apart V-shaped slits 26 which extend in an axial directioninwardly from the small end of the retaining ring into the body portion24. The V-shaped slits open outwardly towards the smaller end of thetapered body portion 24.

The sealing ring 22 consists of an elastomeric material, for example,neoprene. The body portion of the sealing ring 22 has a hollowcylindrical shape where the axial length of the body portion 30 issubstantially longer than the axial length of the body portion 24 of theretaining ring 20. Such difference in length is shown more clearly inFIG. 2.

A pipe 32 is inserted in an open end of the male portion 12 as far aspositioning shoulder 34 as shown in FIG. 2. The retaining and sealingrings 20 and 22 are placed together and inserted within female portion14 over the pipe 32 and partially assembled as shown in the top sectionof FIG. 2. The connection is completed when the female portion 14 isrotated in a positive direction to advance the female portion relativeto the male portion in the direction of arrow 36 to form a fluid-tightseal between the surface of the pipe and the connector and retain thepipe 32 within the connector.

The retaining ring 20 has an inside diameter at the smaller end thereofwhich is approximately equal to or slightly greater than the outsidediameter of the pipe 32 so that the retaining ring surrounds the pipe asshown in section in FIG. 2.

The sealing ring 22 has an inside diameter approximately equal to theoutside diameter of the smaller end of the retaining ring because thesealing ring is cylindrical in shape. Due to the elastomeric propertiesof the sealing ring 22, it is easily stretched to fit over the outsidesurface of the body portion 24 of the retaining ring in the manner shownin FIG. 2 so that the sealing ring is positioned in surrounding andcontacting relationship with the outside surface of the retaining ring.It is understood, however, that the sealing ring may be molded toconform to the varying outside dimensions of the outside surface of thebody portion 24 of the retaining ring. For example, the inside surfaceof the sealing ring may have the shape of the outside surface of atruncated cone. It is also understood that the sealing ring may beintegrally molded with the retaining ring and the molded unit would havea cross-section similar to that of the sealing and retaining ring shownin the top section of FIG. 2.

The female member 14 is provided with a tail piece 38 and the insidesurface thereof merges into an annular shoulder 40. The retaining ring20 has a flange 42 at the larger end 44 thereof where the outsidediameter of the flange 42 is slightly less than the outside diameter ofannular shoulder 40 so that the flange 42 contacts the annular shoulder40 upon advancement of the female member 14 relative to the male member12. The longitudinal axis of the retaining ring is approximatelycoincident with the longitudinal axis of the female member 14. Thesealing ring 22 contacts the inside surface of the flange 42 when theretaining ring is inserted in the sealing ring 22. The flange 42prevents the sealing ring 22 from contacting the annular shoulder 40.

The V-shaped slits 26, define a plurality of gripping teeth 50. Eachgripping tooth 50, has a free end 28, where the circumferential lengthof each free end 28 is sufficient to provide substantially more thanpoint contact with the pipe surface.

As shown in FIG. 3, the incline of the outside surface of the bodyportion 24 of the retaining ring is represented by angle B. The grippingteeth 50 contact the pipe surface at angle B which is a very low contactangle and ranges from approximately 5° to 30° relative to longitudinalaxis of the retaining ring. Correspondingly the annular inwardly slopingsurface 46 is at an angle represented by angle A, as shown in FIG. 2.Angle A may range from approximately 20° to 60° relative to thelongitudinal axis of the male member 12.

The outside diameter of sealing ring 22 is slightly less than thediameter at point 48 on the sloping surface 46, so that the outsidesurface of the sealing ring slidably contacts the annular inwardlysloping surface 46 to exert an inwardly directed force on the grippingteeth 50. As the female member is advanced the sloping surface 46overlaps the gripping teeth 50, in the manner shown in the lower half ofFIG. 2. Due to the low contact angle B with such advancements of thefemale portion 14, the gripping teeth 50 are moved inwardly so as tobring them into contact with the periphery of the pipe 32. With theengagement of the free end 28 of the gripping teeth 50 with the pipeperiphery, the pipe 32 is retained within the connector. It isunderstood of course that upon further advancement of the female member14, the retaining ring is forced further inwardly into the pipe wall andmay, upon sufficient exertion of torque on the collar 14, form anannular depression in the pipe wall. However, due to the low contactangle of the gripping teeth 50, with the periphery of the pipe, theteeth do not substantially gouge or mar the pipe surface, so that theconnector may be disconnected and reconnected without having to cut thepipe end off.

The annular portion 54 of the sealing ring which projects beyond thesmaller end of retaining ring 20 as shown in FIG. 2, is moved inwardlyby the annular inwardly-sloping surface 46 simultaneously with theadvancement of female member 14 in the direction of arrow 36 so that theinside surface of the sealing ring intimately contacts the circumferenceof the pipe to form a fluid-tight seal therearound in the manner shownin the lower portion of FIG. 2. Because of this inward compression ofthe sealing ring 22 around the circumference of the pipe 32, mostdisconformities in the pipe surface, such as indentations, scratches,etc. are sealed by the sealing ring 22 because of the ability of theelastomeric material to accommodate imperfections in the surface of thepipe.

As mentioned hereinabove, the retaining ring 20 may be made from amaterial such as 70/30 half hard yellow brass which, when formed asshown in FIG. 1, has a degree of resiliency, yet it is deformable whensubjected to considerable stress, so that when the elastomeric sealingring 22 exerts an inwardly-directed force on the retaining ring, it maybe slightly deformed as the retaining ring contacts the pipe surface.Upon taking the connector apart, the retaining ring can be expandedoutwardly to permit removal of the retaining ring from the pipe. Becauseof the low contact angle of the retaining ring relative to the exteriorsurface of the pipe 32, the pipe surface is not extensively marred whenthe connector 10 is tightened properly.

In addition, because of the low contact angle of the retaining ring 20,in other words, angle B of FIG. 3, the connector 10 may be pre-assembledin the condition shown in the upper portion of FIG. 2 and the pipe 32subsequently inserted within the connector as far as positioningshoulder 34 in the male member 12. The female member 14 is tightened toeffect a fluid-tight seal around the exterior surface of the pipe 32.

It is sometimes desirable to pass an electrical current through a metalwater pipe to thaw frozen water in the pipe. The connector according tothis invention permits the passing of electrical current through a metalpipe. The retaining ring permits electrical current to pass from thepipe to the female member 14 because it contacts both the pipe andmember 14. Electrical current can travel onto another pipe becausemember 12 is connected to member 14 so that a similar connection on theother side of member 12 permits an electrical current flow from pipe topipe.

The sealing and retaining means according to this invention provides fora compression type pipe connector which permits sealed connections ofone pipe to another where the enlarged body portion 56 of the malemember 12 as shown in FIG. 2 may be identical on the other side thereofto accommodate a pipe inserted from the other end; or the body portion56 may be connected to a service outlet or the like.

The exterior surfaces of male and female members 12 and 14 are providedwith hexagonal surfaces to permit the use of a pipe wrench in thetightening of the connector 10 to secure the pipe 32 therein.

The features of this reusable connector, namely a retaining ring havingresilient gripping teeth at a low angle relative to the pipe surfacewhere the annular inwardly sloping surface of the connector componentoverlaps a portion of the gripping teeth, provides an inwardly directedforce on the gripping teeth to bring the gripping teeth into contactwith the pipe surface without substantially gouging or marring the pipesurface. The sealing ring surrounds the gripping teeth and covers theslits therein so as to provide a fluid-tight seal around the pipe. Suchan arrangement of the components of this invention provides a reusableconnector for piping.

Although various preferred embodiments of the invention have beendescribed herein in detail, it is understood by those skilled in the artthat variations may be made thereto without departing from the spirit ofthe invention or the scope of the appended claims.

I claim:
 1. In a re-useable compression type pipe connector havingthreaded male and female portions, one of which receives a pipe end; asealing and pipe retaining means comprising a retaining ring consistingof a resilient material and having a hollow, truncated cone shaped bodyportion with a plurality of circumferentially spaced apart slits whichextend in an axial direction inwardly from the smaller end of saidretaining ring into the body portion thereof to define a plurality ofresilient gripping teeth, each having a free end, and a sealing ringconsisting of an elastomeric material and having a tubular shape; saidgripping teeth being disposed at a low angle relative to the pipesurface, said angle ranging from approximately 5° to 30°; the axiallength of said sealing ring being substantially longer than the axiallength of said body portion of said retaining ring; said sealing ringbeing in surrounding and contracting relationship with the outsidesurface of said retaining ring where said sealing ring covers said slitsin said retaining ring; the threaded portion which receives such pipeend having an annular inwardly sloping surface for engaging the outsidesurface of said sealing ring when said connector is assembled on a pipeend, the other portion having an internal shoulder means for engagingsaid body portion of said retaining ring, said annular inwardly slopingsurface overlapping a portion of said gripping teeth so that as saidmale and female portions are threadably engaged to thereby move saidinternal shoulder towards said annular inwardly sloping surface, saidannular inwardly sloping surface engages the outside surface of saidsealing ring and causes an annular portion of said sealing ring to exertan inwardly directed force on said gripping teeth therebeneath to movethem into contact with a pipe surface and simultaneously the annularportion of said sealing ring beyond said gripping teeth is moved intosealing arrangement with such pipe; each gripping tooth free end havinga circumferential length to provide substantially more than pointcontact with a pipe surface, the arrangement of said connector beingsuch that said gripping teeth free ends are precluded from substantiallymarring a pipe surface when said teeth are in contact therewith wherebythe connector is re-useable to form a fluid tight seal around a pipe endpreviously engaged by said connector.
 2. In a compression type pipeconnector of claim 1, said retaining ring consisting of brass.
 3. In acompression type pipe connector of claim 1, said retaining ringconsisting of a plastics material when a plastic pipe is to beconnected.
 4. In a compression type pipe connector of claim 1, saidsealing ring consisting of neoprene.
 5. In a compression type pipeconnector of claim 1, said sealing ring being formed in the shape of ahollow cylinder, the inside diameter of the sealing ring beingapproximately equal to the outside diameter of the small end of the bodyportion of said retaining ring.
 6. In a compression type pipe connectorof claim 1, said retaining ring having V-shaped slits in the bodyportion thereof, said V-shaped slits opening outwardly towards thesmaller end of said retaining ring.